Photo AI

Given the equation: $$x^2 - 4x + q = 0$$ 2.1.1 Determine the numerical value of the discriminant if $q = 4$ - NSC Technical Mathematics - Question 2 - 2023 - Paper 1

Question icon

Question 2

Given-the-equation:---$$x^2---4x-+-q-=-0$$--2.1.1-Determine-the-numerical-value-of-the-discriminant-if-$q-=-4$-NSC Technical Mathematics-Question 2-2023-Paper 1.png

Given the equation: $$x^2 - 4x + q = 0$$ 2.1.1 Determine the numerical value of the discriminant if $q = 4$. 2.1.2 Hence, describe the nature of the roots of the... show full transcript

Worked Solution & Example Answer:Given the equation: $$x^2 - 4x + q = 0$$ 2.1.1 Determine the numerical value of the discriminant if $q = 4$ - NSC Technical Mathematics - Question 2 - 2023 - Paper 1

Step 1

Determine the numerical value of the discriminant if $q = 4$.

96%

114 rated

Answer

The discriminant (riangle riangle) of a quadratic equation is calculated using the formula:

riangle=b24ac riangle = b^2 - 4ac

Substituting the values from the equation x24x+q=0x^2 - 4x + q = 0, where a=1a = 1, b=4b = -4, and q=4q = 4, we get:

riangle=(4)24(1)(4) riangle = (-4)^2 - 4(1)(4)

Calculating this gives:

riangle=1616=0 riangle = 16 - 16 = 0

Thus, the numerical value of the discriminant is 00.

Step 2

Hence, describe the nature of the roots of the equation.

99%

104 rated

Answer

Since the discriminant is 00, this indicates that the quadratic equation has exactly one real root (or a repeated real root). This means the roots are equal.

Step 3

Determine the numerical value(s) of $p$ for which the equation $x^2 - 4x + p = 0$ will have non-real roots.

96%

101 rated

Answer

For the roots of the quadratic equation to be non-real, the discriminant must be less than 00:

riangle=b24ac<0 riangle = b^2 - 4ac < 0

Using a=1a = 1, b=4b = -4, and letting c=pc = p, we have:

riangle=(4)24(1)(p)<0 riangle = (-4)^2 - 4(1)(p) < 0

This simplifies to:

164p<016 - 4p < 0

Solving for pp yields:

16<4p16 < 4p

Dividing both sides by 44 gives:

p>4p > 4

Thus, the numerical value(s) of pp for which the equation will have non-real roots is p>4p > 4.

Join the NSC students using SimpleStudy...

97% of Students

Report Improved Results

98% of Students

Recommend to friends

100,000+

Students Supported

1 Million+

Questions answered

;